Magnetic head having fuse within head case

ABSTRACT

A magnetic head usable in a reader-writer for reading and writing data which can be magnetically processed. The magnetic head is characterized in that: it comprises a core (1), an exciting coil (2) for exciting the core (1), and a head case (3) for tightly enclosing the core (1) and the exciting coil (2); and a fuse is provided in a part of the exciting coil (2). When the reader-writer in which the magnetic head is incorporated is to be abandoned, the magnetic head can be easily destroyed, thereby enabling the prevention of fraudulent uses, such as the forging, of magnetic cards.

TECHNICAL FIELD

The present invention relates to a magnetic head usable in areader-writer for reading and writing magnetically recorded data fromand into a magnetic card, etc.

BACKGROUND ART

In recent years, among magnetic cards for recording information in theform data that can be magnetically processed, an increased number ofsuch cards have come to include in their use, in addition to the readingof data recorded, the rewriting of data during the use of the magneticcard. Magnetic cards of this type are, for example, prepaid cards whichallow the remaining units of use, the remaining amount of money, etc. tobe rewritten each time the card is used.

Hitherto, data on a magnetic card of this type has been rewritten in thefollowing manner: first, the present data is read, then new data isoverwritten on magnetic stripes.

As magnetic cards of this type become popular, however, such false actsas forging or copying data on magnetic cards have come to be conducted.

In view of such acts, the card manufacturers have taken counter measuressuch as to cover a magnetic card with a magnetism concealing layer so asto prevent stealing, forging, etc. of data on the magnetic card. Thefact that it is usually difficult for people in general to obtain amagnetic head capable of writing data in a magnetic card, helps toprevent forging of magnetic cards.

However, because a reader-writer for a magnetic card, which is employedduring the use of a magnetic card, has a magnetic head capable ofwriting data, there is a risk that a magnetic head may be obtained froman abandoned reader-writer or the like, and be used in the forging ofmagnetic cards.

The present invention is intended to overcome said problemconventionally encountered, and to provide a magnetic head for areader-writer that is effective for preventing forgery, etc. of data inmagnetic cards.

DISCLOSURE OF INVENTION

According to the present invention, there is provided a magnetic headusable in a reader-writer for reading and writing data which can bemagnetically processed, the magnetic head is characterized in that: itcomprises a core, an exciting coil for exciting the core, and a headcase for tightly enclosing the core and the exciting coil; and a fuse isprovided in a part of the exciting coil.

By virtue of the above-specified arrangement, when a reader-writer inwhich the magnetic head is incorporated is to be abandoned, the magnetichead can be easily destroyed, thereby enabling the prevention offraudulent uses, such as the forging, of magnetic cards.

BRIEF DESCRIPTION OF DRAWING

FIG. 1 is a schematic diagram of a magnetic head according to anembodiment of the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION

An embodiment of the present invention will now be described withreference to the single drawing.

A magnetic head according to one embodiment of the present inventioncomprises, as shown in the drawing, a core 1 for generating a magneticfield, an exciting coil 2 for exciting the core 1, and a head case 3 fortightly enclosing the core 1 and the exciting coil 2. Terminals 5 and 6are provided at two ends of the exciting coil 2 for supplying current,and are exposed to the outside of the head case 3.

A fuse 4 is provided in a part of the exciting coil 2. Therefore, whencurrent of a magnitude above a certain level is applied to the excitingcoil 2, the fuse 4 is blown so that no current will flow through theexciting coil 2, thereby making it impossible for the magnetic head toread or write data.

In this case, since the magnetic head according to the present inventionis such that the head case 3 tightly encloses the core 1 and theexciting coil 2, it is impossible to recover the function of theexciting coil 2 by accessing the fuse 4 from the outside and replacingit. Thus, once the magnetic head is rendered unusable, it cannot be usedagain.

The terminals 5 and 6 are connected both to a circuit which supplies acurrent for operating the magnetic head and to a fuse blowing circuit 7for causing current of a magnitude greater than the permissible currentof the fuse 4 to flow.

The fuse blowing circuit 7 comprises a power source 8 for generatingcurrent of a magnitude greater than the permissible current of the fuse4, and a switch 9. Therefore, when, for instance, fraudulent use of themagnetic head has been detected, or the associated reader-writer is tobe abandoned, the fuse 4 can be easily blown to thereby destroy themagnetic head.

What is claimed is:
 1. A magnetic head usable in a reader-writer forreading and writing data which can be magnetically processed, themagnetic head being characterized in that:it comprises a core, anexciting coil for exciting said core, and a head case for tightlyenclosing said core and said exciting coil; and a fuse is provided in apart of said exciting coil.
 2. A magnetic head according to claim 1,wherein a fuse blowing circuit is connected for causing current of amagnitude greater than the permissible current of said fuse to flowthereto.